DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed adenocarcinoma of the pancreas

  • Locally advanced, unresectable disease, defined by all of the following:

    • Obvious encasement of the celiac, hepatic, or superior mesenteric artery
    • Encasement of the portal or superior mesenteric vein not amenable to surgical resection
    • Extrapancreatic extension with or without regional lymph node involvement
    • No evidence of distant metastatic disease by staging laparoscopy* NOTE: *Patients determined to be unsuitable for this procedure (e.g., prior abdominal surgery, adhesions, etc.) by a surgeon are allowed to participate provided all other eligibility criteria are met

  • Locally recurrent disease after prior curative surgery allowed provided the following are true:

    • No prior chemotherapy or radiotherapy
    • No evidence of distant metastatic disease by staging laparoscopy* NOTE: *Patients determined to be unsuitable for this procedure (e.g., prior abdominal surgery, adhesions, etc.) by a surgeon are allowed to participate provided all other eligibility criteria are met
• No islet cell pancreatic cancer or lymphoma or sarcoma of the pancreas

• Measurable or evaluable disease

  • Primary pancreatic tumor is considered evaluable and not measurable disease
  • Lymph node mass considered measurable disease
• No known brain metastases

PATIENT CHARACTERISTICS:

Age

• 18 and over

Performance status

• ECOG 0-2

Life expectancy

• More than 12 weeks

Hematopoietic

• WBC ≥ 3,000/mm^3
• Absolute neutrophil count ≥ 1,500/mm^3
• Platelet count ≥ 100,000/mm^3

Hepatic

• Bilirubin ≤ 1.5 mg/dL
• AST and ALT ≤ 2.5 times upper limit of normal

Renal

• Creatinine ≤ 2.0 mg/dL OR
• Creatinine clearance ≥ 60 mL/min

Cardiovascular

• No symptomatic congestive heart failure
• No unstable angina pectoris
• No cardiac arrhythmia

Ophthalmic

• No abnormalities of the cornea based on history (e.g., dry eye syndrome or Sjögren's syndrome)
• No congenital abnormality (e.g., Fuch's dystrophy)
• No abnormal slit-lamp examination using a vital dye (e.g., fluorescein or Bengal-Rose)
• No abnormal corneal sensitivity test (Schirmer test or similar tear production test)

Gastrointestinal

• No Crohn's disease or inflammatory bowel disease that would preclude undergoing external beam radiotherapy
• Able to tolerate oral medication
• No requirement for IV alimentation

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception
• No ongoing or active infection
• No other concurrent uncontrolled illness
• No psychiatric illness or social situation that would preclude study compliance

PRIOR CONCURRENT THERAPY:

Biologic therapy

• Not specified

Chemotherapy

• See Disease Characteristics
• No prior gemcitabine

Endocrine therapy

• Not specified

Radiotherapy

• See Disease Characteristics

Surgery

• See Disease Characteristics

Other

• No prior epidermal growth factor receptor-targeting therapy
• No prior therapy for pancreatic cancer (except surgery)
• No concurrent commercial or other investigational agents or therapies intended to treat the malignancy
• No concurrent combination antiretroviral therapy for HIV-positive patients